Her headcanons are probably the most famous among the mlp community, of course not everyone will agree, and that's ok! My headcanon of her being Indian comes from the fact that India gave rise to several brilliant minds in the scientific and mathematical field who, unfortunately, are not very recognized today.

I wanted to explore more of the Hindu ethnicity in Twilight, but I felt it was unfeasible for the cartoon, since Hindus have an extremely vast and very religious culture and in my opinion, Twilight is an atheist. And despite not believing in religion, she studies it and embraces it as part of her culture.

In the show, she loves studying history and many other areas, so I thought she would study a lot about her own culture and appreciate it in a unique way.

Another headcanon that is practically a consensus in the community is related to Twilight's autism, she was going to be canonized as autistic but this unfortunately did not happen. I take this as canon because in the first seasons she exhibits stereotypical behaviors of an autistic person and is identifiable with other people on the spectrum.